Triply unsaturated 1,3-dioxolanes and process for their preparation



United States Patnt O TRIPLY UNSATURATED 1,3-DIOXOLANES AND PROCESS FOR THEIR PREPARATION Harry A. Stansbury, Jr., South Charleston, and Howard R. Guest, Charleston, W. Va., assignors to Union Carbide Corporation, a corporation of New York No Drawing. Application September 27, 1957 Serial No. 686,583

6 Claims. (Cl. 260-340.9)

This invention relates to 1,3-dioxolanes and to a process for their preparation. More particularly, the present invention relates to triply unsaturated 1,3-dioxolanes and to a process for their preparation.

The compounds of this invention may be represented by the structural formula:

CH2=C-CHO with a doubly unsaturated diol having the formula:

R OH OH R GH2=(|JCHCH(|J=CH2 wherein R and R have the Values previously assigned, at a temperature of from about C. to about 100 C. and

the group consisting preferably from about 20 to about 50 C., a pressure of from about 5 to about 150 p. s. i. a. preferably from about to about 20 p. s. i. a. for a period of from about 0.5 to about 50 hours. The reaction is preferably conducted in the presence of an acidic catalyst, such as hydrochloric acid or sulfuric acid. After the reaction is complete, the catalyst is neutralized and the desired triply unsaturated dioxolanes are recovered by fractional distillation.

The following examples are illustrative.

Example I CH CH3 CH2=CHCHO CH2==CCHOHOHOHJJ=CH2 Acrolein 2,5-dimethyl-1,5-hexadiene-3,4-di0l CH3 OCHC=0H2 CHz=CHC H2O OGHCH=CH2 4,5-dils0propenyl-2- vinyl-1,3d1oxolane Water 2,862,007 Patented Nov. 25, 1958 A mixture of 142 grams of 2,5-dimethy1-1,5hexadiene- 3,4-diol (1 mole) and 3 milliliters of 37 percent hydrochloric acid catalyst (.03 equivalent) was stirred at 25 C.45 C. while 174 grams of 96.4 percent acrolein (3 moles) were added all at once. After stirring for 20 hours at 25 C.30 C., 4.1 grams of anhydrous sodium acetate (.05 equivalent) were added to neutralize the catalyst and 100 milliliters of toluene were also added. The mixture was fractionated under reduced pressure to yield 4,5-diisopropenyl-2-vinyl-1,3-dioxolane having the following properties: boiling range of 55 C.61 C./2 mm. Hg, 12 of 1.4594, specific gravity at 20/ 20 C. of 0.957, purity (determined by analytical 'bromination) of 98.2 percent, percent carbon found 71.9 (theory 73.3),

percent hydrogen found 8.8 (theory 8.9). 'The yield of- 2,4,5-triisopropenyl- 1,3-dioxo1ane Water A solution of 199 grams of 2,5-dimethyl-1,5-hexadiene- 3,4-diol (1.4 moles) and 6 milliliters of 37 percent hydrochloric acid catalyst (.06 equivalent) was fed to 392 grams of methacrolein (5.6 moles) over a period of 20 minutes while stirring at 25 C. After a reaction period of minutes at 25 C., 8.2 grams of anhydrous sodium acetate (0.1 equivalent) were added. The mixture was fractionated to yield 2,4,5-triisopropenyl-1,3-dioxolane having the following properties: boiling range of 66 C.68 C./2 mm. Hg, 11, of 1.4617, specific gravity at 20/20 C. of 0.945, purity (determined by analytical bromination) of 106.5 percent, percent carbon found 73.5 (theory 74.2), percent hydrogen found 9.4 (theory 9.4). The yield of this material, based on the unsaturated diol, was 81 percent.

Example III CI-IFOHOHO CH2=CHCHOHCHOHCH=CHz Acrolein 1,5-hexadiene-3,4-di0l OCHOH=OH2 CH2=CHCH H2O OOHOH=CH2 2,4,5-triviny1-L8-dioxo1ane Water A solution of 5 milliliters of 37 percent hydrochloric acid catalyst (0.05 equivalent) in 171 grams of 1,5- hexadiene-3,4-diol (1.5 moles) was fed to 358 grams of 96.4 percent acrolein (6.0 moles) over a period of 15 minutes while stirring at 25 C.-35 C. After a reaction period of an hour at 30 C, 6.6 grams of anhydrous sodium acetate (.08 equivalent) were added. The mixture was fractionated to yield 2,4,5-trivinyl-1,3-dioxolane having the following properties: boiling range of 37 C.40 C./2 mm. Hg, 12 of 1.4542, specific gravity at 20/20 C. of 0.956, purity (determined by analytical bromination) of 96.5 percent, percent carbon found 70.5 (theory 71.0), percent hydrogen found 8.0 (theory 7.9). The yield of this material, based on the unsaturated diol, was 76 percent.

Example IV I CHFCCHO GHz=OHCHOHCHOHOH=OHz Methacrolein 1,5-hexadiene-3A-diol (3H3 OCHCH=CH2 CH2=0 CH H O OCHCH=CH2 2-iS0pr0peny1-4,fi-clivinyl- 1,3-dioxolane A solution of 4 milliliters of 37 percent hydrochloric acid catalyst (.04 equivalent) in 114 grams of 1,5-hexadiene-3,4-diol (1 mole). was fed to 280 grams of methacrolein (4 moles) over a period of 40 minutes while Water stirring at 25 C.30 C. After a reaction period of one hour at 28 C., 5.7 grams of anhydrous sodium acetate (.07 equivalent) were added to neutralize the catalyst. The mixture was fractionated under reduced pressure to yield 2-isopropenyl-4,5-divinyl-1,3-dioxolane having the following properties: boiling range of 48 C.49 C./2 mm. Hg, 72 of 1.4566, specific gravity at /20" C. of 0.946, purity (determined by analytical bromination) 99.7 percent, percent carbon found 71.9 (theory 72.3), percent hydrogen found 8.5 (theory 8.4). The yield of this material, based on the unsaturated diol, was 76 percent. We claim:

1. A triply unsaturated 1,3-dioxolane having the structural formula:

wherein R and R are selected from the group consisting of hydrogen and lower alkyl.

2. 4,5-diisopropenyl-2-vinyl-1,3-dioxolane.

3. 2,4,5-triisopropenyl-1,3-dioxolane.

4. 2,4,5-trivinyl-1,3-dioxolane.

5. 2-isopropenyl-4,S-divinyl-1,3-dioxolane.

6. The process which comprises reacting an unsaturated aldehyde having the formula:

i CHz=C-CHO with a doubly unsaturated diol having the formula;

v If OH OH 1'2 CH2=COHOH.C=OH2 wherein R and R are selected from the group consisting of hydrogen and lower alkyl at a temperature of from about 0 C. to about C. and a pressure of from about 5 to about p. s. i. a. for a period of from about 0.5 to about 50 hours.

No references cited. 

1. A TRIPLY UNSATURATED 1.3-DIOXOLANE HAVING THE STRUCTURAL FORMULA:
 6. THE PROCESS WHICH COMPRISES REACTING AN UNSATURATED ALDEHYDE HAVING THE FORMULA: 